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Item Dynamic study of composite material shaft in high-speed rotor-bearing systems(2019) Gonsalves T.H.; Mohan Kumar G.C.; Ramesh M.R.In this work the composite material shaft in high-speed rotor-bearing systems is analysed to achieve better rotor dynamics along with the effect of internal damping of the composite shaft. The pioneering studies on rotating composite shaft and internal damping are revisited to evaluate its effects on rotor dynamics of high-speed rotor-bearing systems. Two practical rotor-bearing systems are selected to study their suitability for composite shaft application where the composite material is used in the cold section while the existing steel alloy is retained in the hot section as well as at the ends. The rotor dynamic analysis shows significant improvements in rotor dynamics of one of the rotor-bearing systems where the first lateral mode changes to desirable rigid mode from flexure mode shape of existing metallic shaft rotor-bearing system. The frequency values of second and third modes also increase above the operating speed indicating a clear advantage in rotor dynamics. Copyright © 2019 Inderscience Enterprises Ltd.Item Dynamic study of composite material shaft in high-speed rotor-bearing systems(2019) Gonsalves T.H.; Mohan Kumar G.C.; Ramesh M.R.In this work the composite material shaft in high-speed rotor-bearing systems is analysed to achieve better rotor dynamics along with the effect of internal damping of the composite shaft. The pioneering studies on rotating composite shaft and internal damping are revisited to evaluate its effects on rotor dynamics of high-speed rotor-bearing systems. Two practical rotor-bearing systems are selected to study their suitability for composite shaft application where the composite material is used in the cold section while the existing steel alloy is retained in the hot section as well as at the ends. The rotor dynamic analysis shows significant improvements in rotor dynamics of one of the rotor-bearing systems where the first lateral mode changes to desirable rigid mode from flexure mode shape of existing metallic shaft rotor-bearing system. The frequency values of second and third modes also increase above the operating speed indicating a clear advantage in rotor dynamics. Copyright © 2019 Inderscience Enterprises Ltd.Item Influence of extender on Thermo-mechanical Properties of melamine-urea-formaldehyde [MUF] for wood adhesive applications(2019) Nagamadhu M.; Ravi Kumar S.; Suraj R.; Manjunath Iyer K.B.; Mohan Kumar G.C.Now a day's many researchers are trying to build alternative materials for raw wood, by using wood composite materials as an alternative. However, in wood polymer composites major limitations on adhesive materials and its bonding strength effect with economy. In this paper melamine-urea-formaldehyde (MUF) wood adhesive properties were determined over a range of temperature. MUF prepared by considering 1:2.3 weight ratio of urea to the formalin, at 90°C and pH is adjusted to 7.5-8.0 and second urea is added at certain time interval to reduce the formaldehyde emission. MUF has certain properties like flow time, viscosity, solid content, water tolerance, shelf life which is calculated by the observation made. The cost of MUF adhesive can be controlled by adding extender (Maida). As wood polymer composites subjected to over a range of temperature. It's necessary to understand the thermo-mechanical properties of MUF reinforced with Maida as an extender using Dynamic Mechanical Analyzer (DMA). The DMA gives in-phase component like storage modulus, loss modules and tan delta. The results show that storage modulus increases with adding extender even at higher temperature, these shows that by adding extender MUF resist the intermolecular motion. The damping factors were found to be increases by adding extender. Tan delta of MUF exhibiting narrow peak with higher magnitude indicates more energy dissipates, by adding the extender it reduces. The adding extender Maida (MD) water absorption decreases, this shows better MUF having better bonding with extender. © 2019 Elsevier Ltd.Item Effect of drilling parameters on Neem wood veneer epoxy composites using grey relational analysis(2019) Jaiprakash M.; Nagamadhu M.; Karthikeyan K.; Kiran; Shariff M.; Mohan Kumar G.C.In recent trend the composites based wood are replacing the normal wood and other materials in various fields. The wood composites have cosmic properties like cheaper in cost, denser, free from defect, they can be machined in any way to make desired output product. This paper is all about investigation of wood properties and its behavior for drilling process. Drilling is one of the universal machining process that being carried out in the world.The purpose of drilling is to remove the excess of material from the work piece (specimen) to produce a hole and drilling is the primary process that need to be carried on the specimen to perform other machining operation (boring, reaming and tapping) as drilling got various level of importance in different applications, studying about drilling process and its parameter on different materials is important. This paper is all about the analysis of different drilling parameters such as feed rate (mm/min), spindle speed (rpm), Drill diameter on the quality of drilled hole. To study these factors Grey relation technique and Taguchi analysis is implemented. The result shows that feed rate is the major influencing parameter when compared to other cutting parameter and by selecting the optimal value,the quality of the drilled hole can be improved. © 2019 Elsevier Ltd.Item Dynamic Mechanical Analysis and Thermal Stability of Neem Wood Veneer Plastic Composites(2019) Nagamadhu M.; Vijay Kumar S.; Ravi Kumar S.; Suraj R.; Mohan Kumar G.C.The neem wood veneer is used as core materials in many of the wood structural applications. In this research work, neem wood polymer composite (NWPC) were prepared to understand the effect of weight fraction, stacking sequence, and interfacial bonding between neem wood veneer and epoxy material. NWPC were prepared conventional compression molding and Thermo-mechanical properties of wood epoxy composite samples were investigated by the dynamic mechanical analyzer over the temperature range from 30 to 180°C. Storage modulus (G') and Loss modulus (G") of NWPC samples exhibited significant effect with respect weight fraction of wood veneer. Similarly epoxy has good interfacial bonding agent to enhance the strength of multilayered wood polymer composites. However, the stacking sequence having major changes in dynamic mechanical properties, G' & G" increases along the wood fiber direction with negligible load bearing capacity in transfers direction. By changing the orientation of the wood veneer properties improved in both the direction. Additionally, scanning electron microscopy (SEM) evidently shows the interfacial bonding efficiency. © 2019 Elsevier Ltd.Item Preface: Advances in Mechanical Design, Materials and Manufacture: Proceedings of the Second International Conference on Design, Materials and Manufacture 2019(2020) Mohan Kumar G.C.; Jeyaraj P.[No abstract available]Item Dynamic study of composite material shaft in high-speed rotor-bearing systems(Inderscience Publishers, 2019) Gonsalves, Thimothy Harold; Mohan Kumar G.C.; Ramesh M.R.In this work the composite material shaft in high-speed rotor-bearing systems is analysed to achieve better rotor dynamics along with the effect of internal damping of the composite shaft. The pioneering studies on rotating composite shaft and internal damping are revisited to evaluate its effects on rotor dynamics of high-speed rotor-bearing systems. Two practical rotor-bearing systems are selected to study their suitability for composite shaft application where the composite material is used in the cold section while the existing steel alloy is retained in the hot section as well as at the ends. The rotor dynamic analysis shows significant improvements in rotor dynamics of one of the rotor-bearing systems where the first lateral mode changes to desirable rigid mode from flexure mode shape of existing metallic shaft rotor-bearing system. The frequency values of second and third modes also increase above the operating speed indicating a clear advantage in rotor dynamics.Item No Access Influence of glutaraldehyde on dynamic properties of poly(vinyl alcohol) polymer(ICE Publishing, 2020) Mohan Kumar G.C.; Pitchaimani, J.; Nagamadhu, M.This study investigated the dynamic mechanical properties of poly(vinyl alcohol) (PVA; (CH2CH(OH)) n ) cross-linked with glutaraldehyde (GA; OHC(CH2)3CHO). The cross-linked polymer was prepared by using a conventional casting technique and then treated with sulfuric acid (H2SO4) for 24 h. The flexural properties during static and dynamic modes were studied using a three-point bending condition. The static flexural properties are improved with the addition of 30% GA in PVA, with higher value of strain. It was observed that the dynamic mechanical properties of PVA improved significantly with an increase in cross-linking percentage. The storage and loss moduli increased drastically with the addition of the cross-linker up to 20%, and marginal changes occurred with further addition of the cross-linker. The fracture behavior was transformed from ductile to brittle for more than 20% cross-linker. Shifting of the rubber region and liquid region with higher temperatures was observed in storage and loss modulus plots. Improvement in the adhesion factor, cross-linking density and effectiveness was observed for GA up to 25%. The test duration was estimated using the Williams–Landel–Ferry model for different temperatures. The major changes were in the modulus in the rubbery plateau region. The cross-linked polymer had much greater storage and loss moduli, indicating a closer network structure and higher stiffness.